This article is adapted from Mark Schapiro's new book Exposed: The Toxic Chemistry of Everyday Products and What's at Stake for American Power (Chelsea Green).
Into the playrooms of children has come the unsettling news: those little red trains and other neat miniatures of the adult world may be coated in paint containing illegally high levels of lead, posing myriad risks to a child's neurological development. After that discovery prompted a mass recall this past summer, parents will never look at Thomas the Tank Engine the same way again. But the uproar over banned substances and rogue Chinese toy manufacturers has overshadowed an even more troubling issue: the toxins in toys that are perfectly legal. The United States remains one of the few developed countries to permit the import of plastic toys made with polyvinyl chloride additives called phthalates (pronounced tha-lates), which help make toys soft and pliable enough to be twisted or sucked yet durable enough to survive a 1-year-old's grip. A mounting body of scientific evidence suggests that phthalates impede the production of testosterone and disrupt the sexual development of infant boys.
That disturbing claim certainly caught my attention as I sat in a hearing room in the California Capitol January 10, 2006, and watched two of America's leading experts on the physiological effects of chemical exposure testify before the health committee of the State Assembly. Such hearings are normally dry affairs, but the scientists' allegations that children were gnawing and sucking on toy animals and other doodads that decrease production of the male sexual hormone gave the testimony a certain urgency. The experts had been called in by Democratic Assemblywoman Wilma Chan, author of a bill to ban phthalates from children's toys; the bill had been met by powerful opposition from the toy and plastics industries.
In the average home, phthalates are everywhere--in shower curtains, shampoo bottles, raincoats and perfumes (to aid adherence to the skin). In hospitals, they're in medical tubing. A component of that distinct "new car smell" comes from phthalates in the plastic dashboard. The dash becomes more brittle as the car ages because phthalates are slowly migrating into the car's interior. As they sweat out of the plastic, residue enters the air or, through direct contact, the skin.
For infants, the most vulnerable population, exposure takes multiple routes: phthalates enter the womb through the umbilical cord or later through mother's breast milk. Exposure can come from dust in the air, from plasticized wall coverings or flooring and from decaying resins in plastic containers. It can also come from sucking on plastic toys. Plastic rubber duckies floating in many American bathtubs are squishy because of phthalates. Infants, according to the Intergovernmental Forum on Chemical Safety, an affiliate of the World Health Organization, have far less capacity for detoxifying chemicals than do adults, and with toys they face all three points of a "risk triangle": "increased vulnerability" to a chemical's "toxic effects" and plenty of possibilities for exposure through "intimate contact."
Chan's bill also proposed a toy ban on Bisphenol A, but most of the scientists' attention that day was focused on a phthalate called Di(2-ethylhexyl) Phthalate, or DEHP, which when ingested can impede the production of LH, a hormone responsible for triggering cells in the testes to produce testosterone. In a baby boy, testosterone plays a major role in determining everything from gender-based behavior to sex drive to what his sperm count will be twenty years later.
Dr. Earl Gray, who has been studying the effect of endocrine-disrupting chemicals on rodents for seventeen years at the EPA's research facility in Research Triangle Park, North Carolina, told the panel that sexual malformations may follow from below-normal LH and testosterone levels. Dr. Gray has found that rats fed phthalates during pregnancy gave birth to a high rate of male pups with incompletely descended testes and a rare condition known as hypospadias--an opening in the penis elsewhere than on the tip. Both are symptoms of low testosterone. Scientists, Dr. Gray said, were calling these deformities "phthalate syndrome," and they are increasingly concerned about a parallel syndrome in human infants. Declining sperm counts among US men and the rising incidence of conditions like hypospadias and testes cancer, Dr. Gray explained, are the possible outcome of early phthalate exposure. "The research," he said, "suggests more and more concern about phthalates."
Also testifying that day was Dr. Shanna Swan, director of the Center for Reproductive Epidemiology at the University of Rochester School of Medicine, in New York. Dr. Swan conducted a study, published in the June 2005 Environmental Health Perspectives, that sent shock waves through the medical community. Swan took urine samples from 134 pregnant women in Los Angeles, Minneapolis and Columbia, Missouri, and tested them for phthalates. The results showed an apparent correlation between women who had higher phthalate levels in their urine and the fact that their male children, within thirteen months of birth, showed "reduced ano-genital distance (AGD)." That measurement of the distance between the anus and the scrotum is a means of distinguishing between male and female rodents and is a key indicator of testosterone levels. Dr. Gray has been seeing shorter AGDs in rats fed phthalates--now Dr. Swan was seeing it in humans.
Dr. Swan summarized this in layman's terms for the committee: "Wherever we've looked," she said, "human studies are consistent with rodent studies. Phthalates are making the ano-genital distance shorter, in a more feminine direction."